Seek - Firefox Extension

Seek 1.0 extension to Mozilla Thunderbird from David Huynh on Vimeo

This is seriously something I have been wanting for ages! I always feel like I want to search my email like this. Sadly, I've moved away from the fat client email approach towards using Gmail instead. So, I guess I will have to wait for Gmail to add this feature in the future or see if I (or someone else) can implement a web based version of it with their API's.